text: #include <Storages/MergeTree/MergeTreeBlockOutputStream.h>
  #include <Storages/StorageMergeTree.h>
  #include <Interpreters/PartLog.h>
  
  
  namespace DB
  {
  
  Block MergeTreeBlockOutputStream::getHeader() const
  {
      return storage.getSampleBlock();
  }
  
  
  void MergeTreeBlockOutputStream::write(const Block & block)
  {
      storage.delayInsertOrThrowIfNeeded();
  
      auto part_blocks = storage.writer.splitBlockIntoParts(block, max_parts_per_block);
      for (auto & current_block : part_blocks)
      {
          Stopwatch watch;
  
          MergeTreeData::MutableDataPartPtr part = storage.writer.writeTempPart(current_block);
          storage.renameTempPartAndAdd(part, &storage.increment);
  
          PartLog::addNewPart(storage.global_context, part, watch.elapsed());
  
          /// Initiate async merge - it will be done if it's good time for merge and if there are space in 'background_pool'.
          if (storage.merging_mutating_task_handle)
              storage.merging_mutating_task_handle->wake();
      }
  }
  
  }
  